Native Turf: The shocking amount of air pollution produced by one hour of mowing
A riot of wildflowers covering the median in a major street near my neighborhood made me smile every time I drove past it. Then the city mowed it, leaving a flat, lifeless stretch. I’ve seen this happen along roadsides in the city and out in the country, too. I think it’s time we question our mowing habit.
The EPA estimates that Americans spend more than three-billion hours using lawn and garden equipment each year. That use represents a significant source of air pollution, including carbon monoxide, hydrocarbons and nitrogen oxides.
In fact, according to the agency, one hour of mowing produces the same amount of air pollution as driving 11 cars for an hour. While new regulations mean cleaner lawn and garden equipment, it could be a while before everyone switches over to the newer, better stuff. Our mowers also use millions of gallons of gas each weekend, and we spill small amounts refilling them that add up to a significant amount each year.
The mowing of our roadsides and public areas also consumes fuel, creates harmful emissions, costs money and reduces the potential benefits of the landscape. We can’t simply stop mowing existing turf, of course. But we can take steps to transform turf that needs to be mown into native grasses that don’t.
Healthy native vegetation along roads offers many benefits: It reduces erosion, slows water run-off, improves water quality, removes particulates from the air, reduces heat island effect from pavement and sequesters carbon.
One hour of mowing produces the same amount of air pollution as driving 11 cars for an hour.
Native landscapes provide much-needed food and shelter for wildlife, too. Research shows, for example, that 96 percent of non-wetland birds in the U.S. rely on native plants and the insects those plants support.
Yards, roadsides and parks with native habitat, says Susan Reiff, director of the UT Lady Bird Johnson Wildflower Center, can create connectivity between larger pieces of habitat. With natural habitat so fragmented, that can be a key to survival for some species.
Humans benefit, too. Native landscapes use less water and require fewer chemicals such as pesticides and fertilizers. That saves us money, and because natives require less mowing and trimming, it saves energy as well.
So why do we remain wedded to neatly mown turf? Primarily because manicured landscapes have been the standard for decades. People tend to complain when public areas aren’t manicured, and the neighbors look askance when your lawn isn’t. But it wasn’t always thus.
The entire middle section of the U.S. was once covered in prairie, a vibrant mix of grasses and forbs about a foot tall that bloomed in spring and fall. Less than 0.1 percent of that prairie remains, according to Mark Simmons, restoration ecologist at the Wildflower Center. The Mueller Austin development features a 30-acre prairie restoration, created in cooperation with the Center, which offers a tiny glimpse of how beautiful natural prairie can be. Thanks to a little time and education, residents there took ownership of their mixed-grass and tallgrass prairie savannah neighbor. That prairie goodwill could spread.
Some people want public areas mown to keep down so-called undesirable wildlife. But one person’s "undesirable" is another’s "way-cool," and a healthy mix of species is beneficial to the overall system. Spiders, for example, eat other insects. Snakes keep rodents in check. Rodents provide prey for hawks and owls as well, and move and store seeds. In a healthy native ecosystem, none of these critters become too numerous and aren’t likely to bother people, either. If you’ve seen a snake crossing the hike and bike trail from the wildflower area at Lady Bird Lake, it was probably just headed for a drink. Leave it alone and, just like your grandpa said, it will leave you alone, too.
We can come to see “undesirable” wildlife as natural, and un-manicured areas as beautiful. Small touches can help. Mown paths through wildflower areas make them look more purposeful and maintained, for example, and rocks and borders or fences make an area look intentional, rather than neglected.
The Chicago Parks District uses educational signs at native prairies in its city parks. Signs explain where turf grass is being removed, or where a cover crop is in place and being mown to allow native grasses to take hold, and signs identify the native habitat, its uses, and history. Surely Austin shouldn't be out-natived by Chicago.
For homeowners, both the National Wildlife Federation and Texas Parks and Wildlife Department offer certified habitat yard programs that include signs, which help legitimize an untraditional yard for skeptical neighbors. Having a sign in your yard says “this was done on purpose.” When people ask questions, a homeowner has the chance to say why the approach is beneficial.
Along Texas roads, mowing is necessary to provide visibility and a place to safely pull off the road. But this requires only about a car width, except perhaps around crossovers and intersections. Mowing only this strip could significantly reduce the amount of land mown, and the time and energy used on mowing.
Less mowing means fewer emissions, reduced energy use and lower maintenance costs. That's plenty of motivation to change our habits.